Adaptation and Reuse in Designing Web Information Systems

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Adaptation and Reuse in DesigningWeb Information
Systems

• Flavius Frasincar
• flaviusf_at_win.tue.nl
• Peter Barna
• Geert-Jan Houben
• Zoltan Fiala
• Dresden University of Technology

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Contents

• Problem
• Hera-AMACONT Presentation Methodology
• Conceptual Model (CM)
• Application Model (AM)
• Presentation Model (PM)
• Adaptation in CM, AM, and PM
• Reuse in CM, AM, and PM
• Conclusions

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Problem

• Support the design of Web Information Systems
  (WIS) that need to fulfill complex requirements
  universal accessibility, personalizability,
  reusability, interoperability, maintainability,
  evolvability etc.
• Universal accessibility same information on
  different Web platforms
• (e.g. Desktop, Palmtop, WAP Phone, Web TV)
• Personalizability adapt presentation based on
  user features
• (e.g. user preferences, type of user Expert,
  Average, and Beginner)
• Reusability reuse WIS components in other WIS
• Interoperability support information exchange
  between WIS components (inside a system or
  between systems)

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Solution Hera-AMACONT

• Hera-AMACONT is a methodology for hypermedia
  presentation design (part of Web Information
  System design)
• model-based methodology
• (maintainability, evolvability, reusability)
• prototype with a component-based implementation
• (maintainability, evolvability, reusability)
• supports user/platform adaptation of the
  presentation
• (universal accessibility, personalizability)
• uses Semantic Web technologies (RDF(S)) for
  system specification
• (interoperability, reusability)

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Adaptation/Reusability

• Adaptation
• Profile to store device capabilities and user
  preferences
• Conditioning the appearance of design models
  elements based on a profile (overlay models
  presence/absence of an element in a model implies
  its presence/absence in all subsequent models)
• Inheritance
• Reusability
• Inheritance
• Implementation
• Define condition property in RDF(S)
• Use rdfssubClassOf and rdfssubPropertyOf
• XSLT/JavaJena transformations for adapting
  models

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Conceptual Model (CM)

• Provides a uniform semantic view over different
  data sources that are integrated within a given
  Web application
• Consists of hierarchies of concepts relevant
  within the given domain
• Concept properties are
• Attributes refer to media items that
  characterize a concept
• Relationships refer to other concepts
• Media Model defines the media types (based on
  MPEG-7)

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Media Model (MM)
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Example CM
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Example Reuse in CM
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Example Adaptation in CM/MM
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Application Model (AM)

• Captures the logical (navigational) aspects of
  the presentation
• Based on the concept of slice, a meaningful
  presentation unit which contains attributes and
  possibly other slices
• A slice is associated to a concept from CM
• Slice properties are
• Aggregation properties embed a set of slices
  (abstraction for index, tour, indexed guided tour
  etc).
• Reference properties link abstraction

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Example AM
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Example Reuse in AM
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Example Adaptation in AM
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Presentation Model (PM)

• Defines the look-and-feel of the presentation
• Focuses on layout managers
• Overlay layout, Box layout (x/y), Border layout
  (North, West, Center, East, and South), and Grid
  layout (table)
• A layout is associated to a slice or an access
  element (set) from AM
• Layout properties are
• References to slices or access elements from AM
• Attributes for
• Layout e.g. for Box layout axis (x or y)
  (horizontal or vertical arrangement)
• Layout elements e.g. halign (left, center,
  or right) horizontal alignment of the element
  inside the layout

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Example PM
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Example Reuse in PM
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Example Adaptation in PM
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Presentation in Browsers
cHTML (Palmtop)
HTML (Desktop)
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Conclusions

• Hera-AMACONT
• Is a model-based methodology that distinguishes
  three models CM/MM (semantics), AM (navigation),
  and PM (layout)
• Supports adaptation and reusability in the
  different models by conditioning the appearance
  of model elements and by using inheritance
• Based on RDF(S), the foundation of the Semantic
  Web
• As future work
• Explore patterns in models to be reused
• Support adaptivity (based on a User Model/Update
  Rules) and user interaction (by means of forms)